Nanostructured materials and photovoltaic devices including nanostructured materials

1. A nanostructured material, comprising: (a) a first nano-network formed from a plurality of Si quantum dots that are at least one of fused and interconnected; and (b) a second nano-network coupled to said first nano-network and formed from a plurality of Ge quantum dots that are at least one of fused and interconnected, said plurality of Si quantum dots having a first peak size that is from about 1 nm to about 20 nm, said plurality of Ge quantum dots having a second peak size that is greater than said first peak size to define a staggered band offset between said first nano-network and said second nano-network, said nanostructured material being configured to absorb light to produce a first type of charge carrier and a second type of charge carrier, said first type of charge carrier separating into said first nano-network in accordance with said staggered band offset and being-transported in said first nano-network, said second type of charge carrier separating into said second nano-network in accordance with said staggered band offset and being transported in said second nano-network, said nanostructured material having an absorption coefficient that is at least 10 3 cm −1 within a range of wavelengths from about 400 nm to about 700 nm.

2. The nanostructured material of claim 1 , wherein said plurality of Si quantum dots are at least one of fused and interconnected to provide a contiguous conductive path for said first type of charge carrier through at least a portion of said first nano-network.

3. The nanostructured material of claim 2 , wherein said plurality of Ge quantum dots are at least one of fused and interconnected to provide a contiguous conductive path for said second type of charge carrier through at least a portion of said second nano-network.

4. The nanostructured material of claim 1 , wherein said plurality of Si quantum dots have said first peak size that is from about 1 nm to about 10 nm.

5. The nanostructured material of claim 1 , wherein said first type of charge carrier corresponds to electrons, and said second type of charge carrier corresponds to holes.

6. The nanostructured material of claim 1 , wherein said first type of charge carrier and said second type of charge carrier are separated at a boundary between said first nano-network and said second nano-network.

7. The nanostructured material of claim 1 , wherein said absorption coefficient is at least 10 4 cm −1 .

8. The nanostructured material of claim 7 , wherein said absorption coefficient is at least 10 5 cm −1 .

9. The nanostructured material of claim 1 , wherein said nanostructured material has a charge carrier recombination time that is at least 1 ns.

10. The nanostructured material of claim 9 , wherein said charge carrier recombination time is at least 10 ns.

11. The nanostructured material of claim 10 , wherein said charge carrier recombination time is at least 100 ns.

12. The nanostructured material of claim 4 , wherein said plurality of Si quantum dots are interconnected via a first plurality of surface ligands, and said plurality of Ge quantum dots are interconnected via a second plurality of surface ligands.

13. The nanostructured material of claim 12 , wherein said first plurality of surface ligands and said second plurality of surface ligands are selected from charge transfer molecular species, Donor Acceptor molecular species, and conjugated molecular species.